Damper device for hydraulic control valve

ABSTRACT

A damper device for a hydraulic control valve includes: a valve body; a damper oil chamber to which one end surface of a spool is faced; an oil reservoir chamber which is adjacent to the damper oil chamber with a partition wall therebetween; and an orifice provided in the partition wall to allow an upper portion of the damper oil chamber to communicate with the oil reservoir chamber. The damper oil chamber and the oil reservoir chamber are disposed in the valve body. The oil reservoir chamber is constructed by closing an opening of a recessed portion formed on an undersurface of the valve body with a top surface of the support member for supporting the valve body. In order to work the orifice in the partition wall by drilling from the opening of the recessed portion, an axis of the orifice is disposed to pass through the opening of the recessed portion. Thus, it is possible to eliminate need for post-treatment after working the orifice, thereby reducing the cost.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an improvement of a damper device for ahydraulic control valve, comprising: a valve body in which a spooldriven by an output force of a linear solenoid unit is fitted; a damperoil chamber to which one end surface of a spool is faced, the damper oilchamber being disposed in the valve body; an oil reservoir chamber whichis adjacent to the damper oil chamber with a partition walltherebetween, the oil reservoir chamber being disposed in the valvebody; and an orifice provided in the partition wall to allow an upperportion of the damper oil chamber to communicate with the oil reservoirchamber; the oil reservoir chamber being constructed by closing anopening of a recessed portion formed on an undersurface of the valvebody with a top surface of the support member for supporting the valvebody.

2. Description of the Related Art

Such a damper device for a hydraulic control valve is already known asdisclosed in, for example, Japanese Patent Application Laid-open No.2002-130513.

In the conventional damper device for the hydraulic control valve, theorifice, which is provided in the partition wall between the damper oilchamber and the oil reservoir chamber, is worked by a drill whichpenetrates through the outer wall of the oil reservoir chamber.Therefore, it is necessary to close a castoff hole remained in the outerwall of the oil reservoir chamber, with a closing plug after the orificeis worked. That is, a troublesome post-treatment is required afterworking the orifice.

SUMMARY OF THE INVENTION

The present invention has been achieved in view of the abovecircumstances, and has an object to provide a damper device for ahydraulic control valve which eliminates need for the post-treatmentafter working the orifice, thereby reducing the cost.

In order to attain the above-described object, according to a firstfeature of the present invention, there is provided a damper device fora hydraulic control valve, comprising: a valve body in which a spooldriven by an output force of a linear solenoid unit is fitted; a damperoil chamber to which one end surface of a spool is faced, the damper oilchamber being disposed in the valve body; an oil reservoir chamber whichis adjacent to the damper oil chamber with a partition walltherebetween, the oil reservoir chamber being disposed in the valvebody; and an orifice provided in the partition wall to allow an upperportion of the damper oil chamber to communicate with the oil reservoirchamber; the oil reservoir chamber being constructed by closing anopening of a recessed portion formed on an undersurface of the valvebody with a top surface of the support member for supporting the valvebody; wherein the orifice of the partition wall is placed so that anaxis of the orifice passes through the opening of the recessed portion.

The support member corresponds to a transmission case 2 in embodimentsof the present invention which will be described later.

In addition to the first feature, according to a second feature of thepresent invention, the damper device further comprising a drain passagewhich discharges surplus oil of the oil reservoir chamber is openedabove the orifice.

In addition to the second feature, according to a third feature of thepresent invention, a mounting surface of the support member to the valvebody is inclined so that the axis of the orifice is closer to ahorizontal line.

In addition to the second or third feature, according to a fourthfeature the present invention, the drain passage comprises a drain holewhich is provided in the support member and opened to the top surface,and a drain pipe which rises from an opening of the drain hole andopened above the orifice.

With the first feature of the present invention, the orifice of thepartition wall can be worked by drilling along the axis of the orificepassing through the opening of the recessed portion of the valve body.That is, the castoff hole is not necessary in the process of working theorifice. Accordingly, it is not necessary to perform a troublesomepost-treatment of applying a closing plug or the like after working theorifice, thus contributing to reduction of the cost.

With the second feature of the present invention, the oil, which isdischarged to the oil reservoir chamber from the damper oil chamberthrough the orifice, can be stored up to the opening of the drain oilpassage, which is located at position above the orifice, and thereforethe orifice can be submerged in the oil of the oil reservoir chamber.Consequently, the damper oil chamber is always reliably filled with oil,thereby ensuring a good vibration suppressing function of the damper oilchamber.

With the third feature of the present invention, the axis of theorifice, which is opened into the upper portion of the damper oilchamber, can be made closer to the horizontality by the extremely simplemeans of inclining the surface mounting the support member to the valvebody. Therefore, the discharging efficiency of the air bubbles generatedin the damper oil chamber from the orifice is enhanced, thuscontributing to stabilization of the vibration suppressing function ofthe damper oil chamber.

With the fourth feature of the present invention, oil can be stored sothat the orifice is submerged in the oil owing to the presence of thedrain pipe. Therefore, the oil reservoir chamber, and thus the valvebody, can be made compact while ensuring good vibration suppressingfunction of the damper oil chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a bottom view of a hydraulic control valve according to afirst embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along the line 2-2 in FIG. 1.

FIG. 3 is an enlarged sectional view taken along the line 3-3 in FIG. 1.

FIG. 4 is a sectional view taken along the line 3-3 in FIG. 1.

FIG. 5 is a view corresponding to FIG. 4, showing a second embodiment ofthe present invention.

FIG. 6 is a view corresponding to FIG. 3, showing a third embodiment ofthe present invention.

FIG. 7 is a view corresponding to FIG. 3, showing a fourth embodiment ofthe present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The above-mentioned object, other objects, features, and advantages ofthe present invention will become clear from the detailed description ofa preferred embodiment with reference to the accompanying drawings.

The first embodiment of the present invention shown in FIG. 1 to FIG. 4will be explained.

Referring to FIG. 1, a hydraulic control valve 1 is for controllingclutch hydraulic pressure in, for example, an automatic transmission foran automobile, and is constituted of a linear solenoid unit S and avalve unit V. A valve body 20 of the valve unit V is joined with a bolt5 to a top surface 2 a of a transmission case 2 (see FIG. 4) of anautomobile.

As shown in FIG. 2, the linear solenoid unit S includes: a housing 3made of a magnetic material in a bottomed cylindrical shape with one endopened; a coil assembly 4 housed in this housing 3; a cylindrical yoke 6integrally connected to a closed end wall of the housing 3 and placedinside the coil assembly 4; a fixed core 7 connected to the open end ofthe housing 3, and placed inside the coil assembly 4 to oppose to theyoke 6 with a predetermined space from the yoke 6; and a movable core 8slidably fitted in the yoke 6 and the fixed core 7. The coil assembly 4is constituted of a bobbin 9 made of a synthetic resin, a coil 10 whichis wound around the bobbin 9, and a coil case 11 made of a syntheticresin formed to house the bobbin 9 and the coil 10. A coupler 12protruding outside the housing 3 is integrally connected to one endportion of the coil case 11, and a connecting terminal 13 leading to thecoil 10 is placed in the coupler 12.

An opposing surface of the yoke 6 to the fixed core 7 is formedperpendicularly to the axis of the yoke 6. An opposing surface of thefixed core 7 to the yoke 6 is formed into a conical shape.

An output rod 14 penetrating through a central portion of the movablecore 8 is fixed to the movable core 8. One end portion of this outputrod 14 is slidably supported in a bag-shaped first bearing hole 15 ₁provided in the closed end wall of the housing 3 via a first bush 16 ₁.The other end portion of the output rod 14 is slidably supported in asecond bearing hole 15 ₂, which penetrates through a central portion ofthe fixed core 7, via a second bush 16 ₂.

Thus, an electromagnetic thrust force proportional to a current valuepassing through the coil 10 can be applied to the output rod 14 via themovable core 8.

The first bush 16 ₁ is fixed to an inner peripheral surface of the firstbearing hole 15 ₁ by press fitting. A first communication groove 17 ₁ isprovided in the axial direction on an outer peripheral surface of thefirst bush 16 ₁ to provide communication between its opposite endssurfaces. A second bush 16 ₂ is fixed to an inner peripheral surface ofthe second bearing hole 15 ₂ by press fitting. A second communicationgroove 17 ₂ is also provided in the axial direction on an outerperipheral surface of this second bush 16 ₂ to provide communicationbetween its opposite ends surfaces. A third communication groove 17 ₃ isprovided in the axial direction on an outer peripheral surface of themovable core 8 to provide communication between its end surfaces of themovable core 8.

Next, as shown in FIG. 3, the valve unit V is constructed by a valvebody 20 connected by crimping to the housing 3 at the side of the fixedcore 7, a spool 22 which is fitted into a valve hole 21 formed in thisvalve body 20 coaxially with the output rod 14 and abuts to a front endof the output rod 14, a return spring 23 for biasing this spool 22 inits retreating direction, namely, in a direction to abut to the outputrod 14, and a plug 24 which is press-fitted into the valve body 20 andsupports an outer end of the return spring 23. A set load of the returnspring 23 is adjusted in accordance with press fitting depth of the plug24 into the valve body 20.

The spool 22 is provided with a first land portion 25 ₁, a first annulargroove portion 26 ₁, a second land portion 25 ₂, a second annular grooveportion 26 ₂ and a third land portion 25 ₃ in order from the side of thelinear solenoid unit S. The first and the second land portions 25 ₁ and25 ₂ are formed to have the same diameter, and the third land portion 25₃ is formed to have a diameter slightly larger than that of the secondland portion 25 ₂.

Meanwhile, the valve hole 21 of the valve body 20 is provided with anoperating chamber 30 which the abutting portion of the output rod 14 andthe spool 22 faces, a first annular land portion 31 ₁ which is adjacentto this operating chamber 30 and to which the first land portion 25 ₁ isalways slidably fitted, a second annular land portion 31 ₂ which theopposing end portions of the first land portion 25 ₁ and the second landportion 25 ₂ are alternately fitted to and separated from, a thirdannular land portion 31 ₃ to which the second land portion 25 ₂ isalways slidably fitted, a fourth annular land portion 31 ₄ to which thethird land portion 25 ₃ is always slidably fitted, a supply oil chamber32 placed to be sandwiched between the first and the second annular landportions 31 ₁ and 31 ₂, an output oil chamber 33 which is placed insidethe second annular land portion 31 ₂ to be sandwiched between the firstand the second land portions 25 ₁ and 25 ₂ of the spool 22, a drain oilchamber 34 which is placed to be sandwiched between the second and thethird annular land portions 31 ₂ and 31 ₃, a reaction force oil chamber35 which a border portion of the second and the third annular landportions 31 ₂ and 31 ₃ including the second annular groove portion 26 ₂faces, and a damper oil chamber 36 which both opposite ends surfaces ofthe spool 2 and the plug 24 face. The return spring 23 is housed in thisdamper oil chamber 36.

An outer peripheral surface of the third land portion 25 ₃ isconstructed by a cylindrical slide surface 25 _(3a) which is fitted tothe fourth annular land portion 31 ₄, and a taper surface 25 _(3b) whichhas a diameter increasing from the cylindrical slide surface 25 _(3a) tothe reaction force oil chamber 35. A slide gap g which can leak andsupply oil to the damper oil chamber 36 from the reaction force oilchamber 35 is provided between the cylindrical slide surface 25 _(3a) ofthe third land portion 25 ₃ and the fourth annular land portion 31 ₄.

The valve body 20 is further provided with a supply port 37 continuinginto the supply oil chamber 32, an output port 38 continuing into theoutput oil chamber 33, a drain port 39 continuing into the drain oilchamber 34, and a breather port 40 continuing into the operating chamber30. The supply port 37 is connected to a hydraulic pump 42 as ahydraulic pressure source via a supply oil passage 41 of thetransmission case 2. The output port 38 is connected to an output oilpassage 43 directly leading to a hydraulic operating portion 44 such asa clutch for automatic transmission. The drain port 39 and the breatherport 40 are opened into an oil reservoir chamber 49 (see FIG. 1 and FIG.4), which will be described later, inside the valve body 20. Thehydraulic pump 42 is driven by an engine not shown.

The output oil chamber 33 communicates with the reaction force oilchamber 35 via a feedback oil passage 48 formed in the spool 22.

Thus, if the spool 22 is held at the retreated position by the biasingforce of the return spring 23 when the linear solenoid unit S is notenergized, the spool 22 provides communication between the supply port37 and the output port 38. That is, the hydraulic control valve 1 is ofa normally open type.

As shown in FIG. 1 and FIG. 4, the valve body 20 is provided with theoil reservoir chamber 49 around the damper oil chamber 36. The oilreservoir chamber 49 is defined by closing a downward opening of arecessed portion 51 formed in an undersurface of the valve body 20 withthe top surface 2 a of the transmission case 2 to which the valve body20 is joined. An uppermost portion of the damper oil chamber 36 isallowed to communicate with the oil reservoir chamber 49 via an orifice50, so that the oil discharged from the damper oil chamber 36 throughthe orifice 50 is stored in the oil reservoir chamber 49.

The orifice 50 is worked by drilling in a partition wall 20 a betweenthe damper oil chamber 36 and the oil reservoir chamber 46 at an anglediagonally upward from the opening of the recessed portion 51, beforethe valve body 20 is joined to the transmission case 2. In order to makethe drilling work possible, an axis L of the orifice 50 is disposed topass through the opening of the recessed portion 51.

FIG. 4 shows a normal mounting posture of the valve body 20 onto thetransmission case 2. Namely, the valve body 20 is mounted on theinclined top surface 2 a of the transmission case 2 so that a ceilingsurface of the oil reservoir chamber 49 is located above the orifice 50.Such a mounting posture of the valve body 20 is preferable, because theorifice 50, which is diagonally worked by drilling from the side of theopen surface of the recessed portion 51, is brought into a substantiallyhorizontal state, and air bubbles can be smoothly discharged to the oilreservoir chamber 49 from the damper oil chamber 36.

The transmission case 2 is provided with a drain oil hole 52 which opensthe oil reservoir chamber 49 into the oil tank 46 to keep the oilreservoir chamber 49 under atmospheric pressure. In this case, theopening of the drain oil hole 52 to the oil reservoir chamber 49 isplaced above the orifice 50 so that the oil, which moves into the oilreservoir chamber 49 from the orifice 50, is discharged to the drainpassage 52 after the oil is stored sufficiently in the oil reservoirchamber 49 to submerge the orifice 50 in the oil.

Next, an operation of the first embodiment will be explained.

When the linear solenoid unit S is not energized, the spool 22 islocated at a rightward movement limit position (retreat limit) by thebiasing force of the return spring 23 as shown in FIG. 3, so that thespool 22 provides communication between the supply port 37 and theoutput port 38, and provides blockage between the output port 38 and thedrain port 39. Therefore, when the hydraulic pump 42 is driven by theengine to generate hydraulic pressure, the hydraulic pressure istransmitted to the reaction force oil chamber 35 through the supply oilpassage 41, the supply port 37 and the feed back oil passage 48. Then,in this reaction force oil chamber 35, the leftward thrust force withthe magnitude, which is obtained by multiplying the hydraulic pressureby the area difference of the opposing end surfaces between the secondland portion 25 ₂ with the small diameter and the third land portion 25₃ with the large diameter of the spool 22, acts on the spool 22, as thereaction force to resist the biasing force of the return spring 23.

On the other hand, when the coil 10 of the linear solenoid unit S isenergized, the electromagnetic force corresponding to the current valueacts on the spool 22 via the output rod 14 as the leftward thrust force.As a result, the spool 22 moves to a position where the three forces,that is, the leftward thrust force generated in the reaction force oilchamber 35, the leftward thrust force by the electromagnetic force andthe rightward thrust force by the return sprint 23 are balanced, andcontrols the opening degree of the supply port 37. Namely, when thecombined leftward thrust force is larger than the rightward thrustforce, the spool 22 advances leftward, so that the first land portion 25₁ provides blockage between the supply port 37 and the output port 38,and the second land portion 25 ₂ provides communication between theoutput port 38 and the drain port 39. Therefore, the hydraulic pressureof the output port 38 decreases. On the other hand, when the rightwardthrust force becomes larger than the leftward composite thrust force,the spool 22 advances rightward, so that the second land portion 25 ₂provides blockage between the output port 38 and the drain port 39, andthe first land portion 25 ₁ provides communication between the supplyport 37 and the output port 38. Therefore, the hydraulic pressure of theoutput port 38 increases. Since the opening degree of the output port 38is controlled as described above, the hydraulic pressure correspondingto the value of the current applied to the coil 10 is taken out of theoutput port 38, and supplied to the hydraulic pressure operating unit44.

The hydraulic control valve 1 is a normally open type in which thesupply port 37 is normally opened, and therefore, when the hydraulicpump 42 operates, the generated hydraulic pressure is instantly suppliedto the reaction force oil chamber 35 as described above. In addition,the reaction force oil chamber 35 and the damper oil chamber 36 adjacentthereto communicate with each other via the slide gap g between thethird land portion 25 ₃ and the fourth annular land portion 31 ₄.Therefore, when the hydraulic pressure is supplied to the reaction forceoil chamber 35, oil immediately leaks from the reaction force oilchamber 35 to the damper oil chamber 36, to fill the damper oil chamber36 with oil. Accordingly, the damper oil chamber 36 can functionnormally without a delay from the early stage of the operation of thehydraulic control valve 1. Namely, when the spool 22 vibrates, thevibration of the spool 22 can be suppressed by the throttle resistanceof the orifice 50, which occurs when the oil of the damper oil chamber36 moves to and from the orifice 50 following the vibration of the spool22. Therefore, the pulsation of the output hydraulic pressure due to thevibration of the spool 22 is prevented to ensure a stable operationstate of the hydraulic operating unit 44.

When the damper oil chamber 36 is filled with the leak oil from thereaction force oil chamber 35, the surplus oil is discharged from theorifice 50 into the adjacent oil reservoir chamber 49 to be storedtherein. When the oil level of the oil reservoir chamber 49 reaches apredetermined level at which the orifice 50 is submerged under the oillevel, the oil overflows through the drain oil hole 52 to return to theoil tank 46.

As described above, the leak oil is positively supplied to the damperoil chamber 36 from the reaction force oil chamber 35, and the orifice50 is submerged in the oil which is discharged into and stored in theoil reservoir chamber 49 through the orifice 50. Therefore, the damperoil chamber 36 is always reliably filled with oil, and the favorablevibration suppressing function of the damper oil chamber 36 can beobtained. Accordingly, it is not necessary to submerge the damper oilchamber 36 in the oil of the oil tank as in the prior art, therebyeliminating the restriction on the arrangement of the normally openhydraulic control valve to enhance general versatility.

Since the orifice 50 is opened to the uppermost portion of the damperoil chamber 36, the air bubbles generating in the damper oil chamber 36and the oil can be quickly discharged to the oil reservoir chamber 49through the orifice 50, and thus better vibration suppressing functionof the damper oil chamber 36 can be obtained.

Incidentally, the axis L of the orifice 50 is disposed to pass throughthe downward opening of the recessed portion 51 of the valve body 20,and therefore the orifice 50 can be worked by drilling in the partitionwall 20 a between the damper oil chamber 36 and the oil reservoirchamber 46 without interference by the outer wall of the oil reservoirchamber 46. Since a castoff hole is not required, a closing plug forclosing the castoff hole as in the prior art is not required after thedrilling work, thus contributing to reduction in the cost.

Meanwhile, the outer peripheral surface of the third land portion 25 ₃is constructed by a cylindrical slide surface 25 _(3a) which fitted tothe fourth annular land portion 31 ₄, and the taper surface 25 _(3b)which becomes smaller in diameter toward the reaction force oil chamber35 from the cylindrical slide surface 25 _(3a), as mentioned above.Therefore, even when the third land portion 25 ₃ receives side thrustand is moved to one side of the fourth annular land portion 31 ₄ by leakoil passing through the slide gap g between the third land portion 25 ₃and the fourth annular land portion 31 ₄, one side portion of thecylindrical slide surface 25 _(3a) abuts to the inner peripheral surfaceof the fourth annular land portion 31 ₄, but the taper surface 25 _(3b)does not contact the fourth annular land portion 31 ₄ over the entirecircumference. Accordingly, the hydraulic pressure of the reaction forceoil chamber 35 acts on the entire peripheral surface of the tapersurface 25 _(3b) to give an aligning force to the third land portion 25₃, thereby ensuring smooth slide of the third land portion 25 ₃ withrespect to the fourth annular land portion 31 ₄.

Next, a second embodiment of the present invention shown in FIG. 5 willbe explained.

In the second embodiment, the oil reservoir chamber 49 is constructed tobe compact, and a drain pipe 53, which rises at the drain oil hole 52and extends to a position above the orifice 50, is mounted in thetransmission case 2. The other parts of construction are the same as inthe previous embodiment, and therefore the parts corresponding to theprevious embodiment are given the identical reference numerals andcharacters in FIG. 5, and the explanation of them will be omitted.

According to the second embodiment, the oil stored in the oil reservoirchamber 49 does not overflow unless the oil level reaches the upper endof the drain pipe 53, which is located at the position above the orifice50. Therefore, the orifice 50 can be submerged in the oil of the oilreservoir chamber 49, though the oil reservoir chamber 49 is constructedto be compact.

Next, a third embodiment of the present invention shown in FIG. 6 willbe explained.

In the third embodiment, the outer peripheral surface of the third landportion 25 ₃ is constructed by connecting a reduced diameter cylindricalsurface 25 _(3c), which is in place of the taper surface 25 _(3b) of thefirst embodiment, to the cylindrical slide surface 25 _(3a) via anannular step portion. Since the other parts of construction are the sameas in the first embodiment, the parts corresponding to the firstembodiment are given the identical reference numerals and characters inFIG. 6, and the explanation of them will be omitted.

Also in the third embodiment, even when the third land portion 25 ₃receives side thrust for some reason and is moved to one side of thefourth annular land portion 31 ₄, one side portion of the cylindricalslide surface 25 _(3a) abuts to the inner peripheral surface of thefourth annular land portion 31 ₄, but the reduced diameter cylindricalsurface 25 _(3c) does not contact the fourth annular land portion 31 ₄over the entire circumference. Accordingly, the hydraulic pressure ofthe reaction force oil chamber 35 acts on the entire peripheral surfaceof the reduced diameter cylindrical surface 25 _(3c) to give thealigning force to the third land portion 25 ₃, thus ensuring smoothslide of the third land portion 25 ₃ with respect to the fourth annularland portion 31 ₄. The reduced diameter cylindrical surface 25 _(3c) hasan advantage in being easier to work than the taper surface 25 _(3b) ofthe first embodiment.

Finally, a fourth embodiment of the present invention shown in FIG. 7will be explained.

In the fourth embodiment, while forming the cylindrical slide surface 25_(1a) fitted to the first annular land portion 31 ₁ and a cylindricalslide surface 25 _(1a), which is fitted to and separated from the secondannular land portion 31 ₂, a taper surface 25 _(1b) which becomessmaller in diameter toward the cylindrical slide surface 25 _(1a), isformed on the outer peripheral surface of the first land portion 25 ₁.Also in the second land portion 25 ₂, a taper surface 25 _(2b), whichbecomes smaller in diameter toward the reaction force oil chamber 35, isformed at the end portion at the side of the reaction force oil chamber35, while forming the cylindrical slide surface 25 _(2a), which isfitted to the second and the third annular land portions 25 ₂ and 25 ₃.Since the other parts of construction are the same as that in the firstembodiment, the parts corresponding to the second embodiment are giventhe identical reference numerals and characters in FIG. 7, and theexplanation of them will be omitted. In short, in the fourth embodiment,the taper surfaces 25 _(1b) to 25 _(3b) are formed on the outerperipheral surfaces of the first to the third land portion 25 ₁ to 25 ₃.

Accordingly, the hydraulic pressure introduced into the supply oilchamber 32 from the supply port 37 acts on the taper surface 25 _(1b) ofthe first land portion 25 ₁, and therefore the aligning force acts onthe first land portion 25 ₁. The hydraulic pressure of the reactionforce oil chamber 35 acts on the taper surface 25 _(2b) of the secondland portion 25 ₂ as in the taper surface 25 _(3b) of the third landportion 25 ₃, and therefore the aligning force also acts on the secondland portion 25 ₂. Thus, the aligning force is applied to all the landportions 25 ₁ to 25 ₃, thereby ensuring a smooth slide state of thespool 22.

The present invention is not limited to the above-described embodimentsand modifications, and various design changes may be made withoutdeparting from the subject matter of the present invention. For example,the present invention is applicable to a normally closed hydrauliccontrol valve. Oil can be supplied to the damper oil chamber 49 alsofrom the drain port 36.

1. A damper device for a hydraulic control valve, comprising: a valvebody in which a spool driven by an output force of a linear solenoidunit is fitted; a damper oil chamber to which one end surface of a spoolis faced, the damper oil chamber being disposed in the valve body; anoil reservoir chamber which is adjacent to the damper oil chamber with apartition wall therebetween, the oil reservoir chamber being disposed inthe valve body; and an orifice provided in the partition wall to allowan upper portion of the damper oil chamber to communicate with the oilreservoir chamber; the oil reservoir chamber being constructed byclosing an opening of a recessed portion formed on an undersurface ofthe valve body with a top surface of the support member for supportingthe valve body; wherein the orifice of the partition wall is placed sothat an axis of the orifice passes through the opening of the recessedportion.
 2. The damper device for the hydraulic control valve accordingto claim 1, further comprising a drain passage which discharges surplusoil of the oil reservoir chamber is opened above the orifice.
 3. Thedamper device for the hydraulic control valve according to claim 2,wherein a mounting surface of the support member to the valve body isinclined so that the axis of the orifice is closer to a horizontal line.4. The damper device for the hydraulic control valve according to claim2, wherein the drain passage comprises a drain hole which is provided inthe support member and opened to the top surface, and a drain pipe whichrises from an opening of the drain hole and opened above the orifice. 5.The damper device for the hydraulic control valve according to claim 3,wherein the drain passage comprises a drain hole which is provided inthe support member and opened to the top surface, and a drain pipe whichrises from an opening of the drain hole and opened above the orifice.